As we posted the other day, while Safari in iOS 4.3 got a huge speed boost thanks to the Nitro JavaScript engine, asynchronous mode, and HTML 5 caching, bookmarking a site to the Home Screen (Web Clips) that launch in full-screen mode, or browsing inside an app (UIWebView) didn't. That meant, while web apps on the home screen and web pages embedded in apps were as fast as they were in iOS 4.2, they weren't as fast as Safari in iOS 4.3.

The technical reason for this is because Nitro is using Just-in-Time (JIT) compilation. Daring Fireball says:

CNET UK was able to take the iPad 2 running iOS 4.3 out for a test drive and the results are hypercar impressive -- 2097ms. iOS 4.3 and its new Safari Nitro engine gets a lot of the credit -- it blows iPhone 4 and the original iPad past the likes of the Nexus S and Galaxy Tab as well (they've been unable to test a Xoom as of yet), but that Apple A5 is enough to power iPad 2 to very top.

Which has the fastest browser, Apple's iOS 4 or Google's Android 2.2? We're used to browser battles here on TiPb, but how about a browser battle battle? See, both Ars Technica and Engadget ran some tests, pitting iPhone 4 on iOS 4 against the Nexus One running Android 2.2 Froyo and the results... varied dramatically to say the least.

Ars SunSpider and V8 benchmarks showed the Nexus One blowing iPhone 4 out of the water with almost double the JavaScript performance. Engadget's real-world test loading real-world webpages, however, had iPhone 4 with a slight lead when Flash was enabled on the Nexus One, and slightly behind when Flash was disabled.

Apple has just released desktop Safari for Mac and Windows to 4.0.4, which improves full history search performance, has the mandatory stability improvements, and security fixes, but the big news as far as we're concerned is the number one item on the list -- Improved JavaScript performance